(PROJECT TERMINATED) The vascular endothelial cell is uniquely situated to play an active role in the transduction of pro-inflammatory signals from the interstitial tissues to circulating neutrophils. The goals of our principal projects are (i) to study the role of endothelial cell receptor mediated transduction events in response to humoral inflammatory mediators; (ii) to examine the role of the endothelial cell in transduction of chemoattractant signals from interstitial sites to circulating leukocytes; and (iii) to examine the interaction of endothelial cells with neutrophils in the inflammatory response; and (iv) to examine the interaction of endothelial cells with pathogenic microorganisms. We demonstrated that endothelial cells bind formyl peptide chemoattractants, and release them intact. The characteristics of the binding site on endothelial cells differs in affinity and binding specificity from that found on phagocytic cells. The endothelial cell may direct transport of chemoattractant peptides from interstitial sites to the vascular lumen. In other studies we examined the interaction between fungal hyphae and endothelial cells, documenting a protective effect of neutrophils on the endothelial cell damage by fungi.